This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A201483 #6 Sep 08 2022 08:46:01
%S A201483 409,1129,5449,13009,16249,49009,61609,68449,91129,99409,167449,
%T A201483 178609,190129,356449,477409,534649,595129,680809,748849,796009,
%U A201483 820129,844609,920209,972409,999049,1225129,1315849,1378129,1441849,1607449
%N A201483 primes of the form 5n^2 + 4.
%H A201483 Vincenzo Librandi, <a href="/A201483/b201483.txt">Table of n, a(n) for n = 1..5000</a>
%t A201483 Select[Table[5n^2+4,{n,0,2000}],PrimeQ]
%o A201483 (Magma) [a: n in [0..700] | IsPrime(a) where a is 5*n^2+4];
%K A201483 nonn,easy
%O A201483 1,1
%A A201483 _Vincenzo Librandi_, Dec 02 2011